Oxidation of p-xylene to terephthalaldehyde

ABSTRACT

terephthalaldehyde is produced by the vapor phase oxidation of p-xylene in the presence of a catalyst mixture of tungsten in the form of an oxide or silicotungstic acid, molybdenum in the form of an oxide and bismuth in the form of an oxide, wherein the activity of the catalyst is prolonged by contacting the catalyst mixture intermittently or continuously with molybdenum oxide vapor or a compound which forms molybdenum oxide under the reaction conditions.



